The Long Term Evolution (LTE) of wideband code division multiple access (WCDMA) third generation (3G) cellular networks is directed to universal mobile telecommunication systems (UMTS) beyond the third generation partnership project (3GPP) Release 7. LTE may also be referred to as evolved UMTS terrestrial radio access (E-UTRA). One of the main technological challenges of such networks is efficient channel usage when there is a varied traffic mix in the system. This may be particularly challenging when the various types of traffic utilize different transmission protocols, such as voice over internet protocol (VoIP), file transfer protocol (FTP), or hypertext transfer protocol (HTTP). For example, in any particular wireless communication system, there may be numerous VoIP users, FTP users, and HTTP users all transmitting simultaneously.
Additionally, the wireless transmit/receive units (WTRUs) in the system perform a variety of tasks and functions that require access to the transmission medium in order to communicate with a base station. For example, the WTRUs must perform functions such as timing advance, measurement reporting, requesting uplink (UL) physical resource allocation, providing schedule information for downlink (DL) allocation, keep-alive heartbeat, hybrid automatic repeat request (HARQ) feedback and/or Medium Access Control (MAC) or Radio Resource Control (RRC) layer signaling.
The WTRUs in a wireless communication system could utilize a Random Access Channel (RACH) or physical RACH (PRACH) in order to communicate with the base station to perform these functions. However, a RACH is a contention-based channel, and its use incurs delays that tend to affect quality of service (QoS) and may result in inefficient use of physical resources. A reliance on RACH for interactive applications between transmissions may also negatively impact system capacity.
Alternatively, the WTRU could utilize a UL shared channel to perform these functions. However, a UL shared channel resource request would first have to be transmitted on a RACH/PRACH, which would be an inefficient use of resources and would add delay to these functions due to the two step procedure.
In the context of LTE, it would be desirable to utilize an access protocol such as a non-contention based (NCB) channel, which may also be referred to as a “thin” or “dedicated” channel. Thin channels are generally contention-free, or low contention, control channels that are primarily used for access.
It would therefore be advantageous to provide a method and apparatus for providing and utilizing an NCB channel that would not be subject to the limitations of the current state of the art.